Ideas of Alfred Tarski, by Theme
[Polish, 1902 - 1983, Taught in Warsaw 1925-1939, then University of California at Berkeley from 1942 to 1968.]
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1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
19199
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Some say metaphysics is a highly generalised empirical study of objects
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1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
19193
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Disputes that fail to use precise scientific terminology are all meaningless
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2. Reason / D. Definition / 1. Definitions
19179
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For a definition we need the words or concepts used, the rules, and the structure of the language
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3. Truth / A. Truth Problems / 2. Defining Truth
16295
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Tarski proved that truth cannot be defined from within a given theory [Halbach]
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15342
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Tarski proved that any reasonably expressive language suffers from the liar paradox [Horsten]
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19069
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'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless
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10153
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In everyday language, truth seems indefinable, inconsistent, and illogical
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19178
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Definitions of truth should not introduce a new version of the concept, but capture the old one
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19177
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A definition of truth should be materially adequate and formally correct
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19186
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A rigorous definition of truth is only possible in an exactly specified language
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19194
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We may eventually need to split the word 'true' into several less ambiguous terms
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3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
16296
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Tarski's Theorem renders any precise version of correspondence impossible [Halbach]
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3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
15339
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Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Horsten]
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16302
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Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Halbach]
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19135
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Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson]
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19138
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Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson]
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4699
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Tarski made truth relative, by only defining truth within some given artificial language [O'Grady]
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19324
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Tarski has to avoid stating how truths relate to states of affairs [Kirkham]
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10672
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Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Hossack]
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13338
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'"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth
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19180
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It is convenient to attach 'true' to sentences, and hence the language must be specified
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19181
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In the classical concept of truth, 'snow is white' is true if snow is white
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19183
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Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction
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19182
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Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate'
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19198
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We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true
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19196
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Scheme (T) is not a definition of truth
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3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
15410
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Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess]
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18811
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Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Rumfitt]
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15365
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We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Horsten]
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19314
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For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Kirkham]
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19316
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Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Kirkham]
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19175
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Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Davidson]
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19184
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The best truth definition involves other semantic notions, like satisfaction (relating terms and objects)
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19191
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Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects
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3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
19188
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We can't use a semantically closed language, or ditch our logic, so a meta-language is needed
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19189
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The metalanguage must contain the object language, logic, and defined semantics
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3. Truth / F. Semantic Truth / 2. Semantic Truth
10969
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Tarski had a theory of truth, and a theory of theories of truth [Read]
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17746
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Tarski's 'truth' is a precise relation between the language and its semantics [Walicki]
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10904
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Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith]
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2571
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Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Haack]
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10821
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Physicalists should explain reference nonsemantically, rather than getting rid of it [Field,H]
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10822
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A physicalist account must add primitive reference to Tarski's theory [Field,H]
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19134
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Tarski defined truth for particular languages, but didn't define it across languages [Davidson]
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16303
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Tarski made truth respectable, by proving that it could be defined [Halbach]
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16304
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Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach]
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10824
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If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H]
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3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
16306
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Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Halbach]
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15322
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Tarski's had the first axiomatic theory of truth that was minimally adequate [Horsten]
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19141
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Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Davidson]
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19190
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We need an undefined term 'true' in the meta-language, specified by axioms
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3. Truth / H. Deflationary Truth / 1. Redundant Truth
19197
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Truth can't be eliminated from universal claims, or from particular unspecified claims
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3. Truth / H. Deflationary Truth / 2. Deflationary Truth
19185
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Semantics is a very modest discipline which solves no real problems
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4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
19195
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Truth tables give prior conditions for logic, but are outside the system, and not definitions
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5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
10152
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Set theory and logic are fairy tales, but still worth studying
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5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
10048
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There is no clear boundary between the logical and the non-logical
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5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
13337
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A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules
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5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
18812
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Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Rumfitt]
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5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
10694
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Logical consequence is when in any model in which the premises are true, the conclusion is true [Beall/Restall]
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10479
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Logical consequence: true premises give true conclusions under all interpretations [Hodges,W]
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13344
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X follows from sentences K iff every model of K also models X
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5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
19192
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The truth definition proves semantic contradiction and excluded middle laws (not the logic laws)
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5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
18759
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Identity is invariant under arbitrary permutations, so it seems to be a logical term [McGee]
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5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
10823
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A name denotes an object if the object satisfies a particular sentential function
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5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
18756
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Tarski built a compositional semantics for predicate logic, from dependent satisfactions [McGee]
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19313
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Tarksi invented the first semantics for predicate logic, using this conception of truth [Kirkham]
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13335
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Semantics is the concepts of connections of language to reality, such as denotation, definition and truth
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13336
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A language containing its own semantics is inconsistent - but we can use a second language
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5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
13339
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A sentence is satisfied when we can assert the sentence when the variables are assigned
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13340
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Satisfaction is the easiest semantical concept to define, and the others will reduce to it
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5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
16323
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The object language/ metalanguage distinction is the basis of model theory [Halbach]
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13343
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A 'model' is a sequence of objects which satisfies a complete set of sentential functions
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5. Theory of Logic / K. Features of Logics / 2. Consistency
13341
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Using the definition of truth, we can prove theories consistent within sound logics
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5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
8940
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Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Fisher]
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19187
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The Liar makes us assert a false sentence, so it must be taken seriously
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6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
10157
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Tarski improved Hilbert's geometry axioms, and without set-theory [Feferman/Feferman]
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6. Mathematics / C. Sources of Mathematics / 7. Formalism
10154
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Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman]
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8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
10151
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I am a deeply convinced nominalist
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19. Language / E. Analyticity / 1. Analytic Propositions
13345
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Sentences are 'analytical' if every sequence of objects models them
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21. Aesthetics / A. Aesthetic Experience / 3. Taste
20407
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Taste is the capacity to judge an object or representation which is thought to be beautiful [Schellekens]
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